Excessive Cpu Usage By Network Card

[Samrc]

Last week, my supervisor's home PC was stalling out when you tried to do anything.

CPU usage would be 54-71% without opening anything and would go immediately to 100% and hang if you actually tried to use a program.

 

I just reformatted and fresh installed Win XP Home, added drivers, added free zonealarm firewall then updated all drivers and xp fully.

Loaded only the basic software required for the system.

No personal files moved back onto system, no adware/spyware or other yuck. CLEAN.

 

When I have the network card DISABLED in the hardware profile, her system is quiet, using 0-2% of resources, even if on the internet using the dial-up modem.

However, the second I connect her ethernet card, the system immedially jumps to the same CPU usage as before, 54-71%.

Swapped network cards twice, no change, so the card/driver is not the issue directly since all three cards are different brands, all with specific drivers.

Tried the integrated Lan port but it gets the same result...I disabled it in BIOS so it is not interferring with PCI card.

 

Ran Process Explorer which confirmed that the high CPU usuage is caused by hardware interrupts. (love that program!!!)

Checked and found no hardware conflicts.

IRQ18 -PCI is assigned to both the NIC and the USB 2.0 Enhanced Host Controller (these are default settings).

Her motherboard is a Gigabyte brand with AMD processor.

 

The rest of the hardware is solid and seems a shame to get rid of the system because she can't use high-speed internet on it without overloading the system! She needs to be able to get into our office machine with the home machine so high-speed is a necessity for her.

So... anything I can do to remedy this? Any suggestions?

Edited August 20, 2007 by Samrc

[TCH-James]

Have you tried disabling the USB 2.0 through the BIOS, or moving the NIC card to a different PCI slot?

 

On an older machine of mine, I had to have the cards in certain slots or there would be issues with the hardware conflicting. My issue is that one of the cards would just not show up, but it may be worth a try for you.

[Madmanmcp]

I would check to see if its some internet activity going on in the background. Is the computer infected with a worm, backdoor, IRC bot? Is there some type of "update" being download and installed. I've had times where the system were running terribly slow and found that my Security programs or Microsoft were downloading and installing the updates in the background. Once they completed the system was fine.

[Samrc]

I would check to see if its some internet activity going on in the background.

Nothing going on in background. No worm or other infections. Reformatted hard drive, clean reinstall, no programs or documents from previous state have been put on the new installation. Have the same CPU usage even when cable is unplugged, and no traffic when cable IS plugged in.

And there is no increase of CPU usage or excess traffic when on dialup. Retains low CPU usage even when connected to web and surfing.

 

Is there some type of "update" being download and installed

Nope. All windows updates done, all basics accomplished. No change.

 

Have you tried disabling the USB 2.0 through the BIOS, or moving the NIC card to a different PCI slot?

Yes, I tried both PCI slots. Same result.

I have not disabled USB 2.00 through BIOS. Will give that a try but don't hold out much hope.

 

 

Wackiest thing. Really thought the reformat and reload would resolve the problem. Thought it was related to Windows file corruptions. But it isn't.

She replaced her motherboard a year ago...maybe this one has a problem too....??? Have spent a good part of my weekend on it. Maybe just give her bad news, pronouce this one DOA and get new PC?

Edited August 21, 2007 by Samrc

[Madmanmcp]

Ran Process Explorer which confirmed that the high CPU usuage is caused by hardware interrupts.

 

I've read where a high amount of hardware interrupts could be a sign of hardware failure. You probably removed the possibility of a bad card by using several different ones and the possibility they all are failing is slim. That would leave the slots and the MB itself. I would have suggested that you check for updated nic drivers but again, the use of several cards and loading each one's drivers would rule that out also.

[Samrc]

I've read where a high amount of hardware interrupts could be a sign of hardware failure.

Yes, I have read that too.

 

I think I am down to only the motherboard dying after ruling out:

- Windows corruptions

- PCI network card (I used 3 w/3 drivers)

- onboard lan port and original driver

- swapping PCI slots

- reseated the ram (just in case)

- tested the modem

 

I know of no way to bypass a bad motherboard...Drives you can replace or just unplug and remove from BIOS. But if Mamma ain't happy, ain't nobody happy.

 

Thanks for the input and confirmation that I didn't leave anything else out.

I will let her know I am taking the patient off life support.